The present invention relates to an apparatus for storing and selectively dispensing sterile liquids from a sealed container disposed within a housing which has a spring mechanism for pressurizing the liquid within the container.
Relatively recent developments in contact lenses have produced a contact lens which is manufactured from soft, pliable materials. These soft contact lenses offer many desirable features to the wearer, such as: extended period wear, increased comfort, oxygen permeability, etc. These features have proved to be extremely popular with a large segment of the populace who wear vision correcting apparatus such as hard contact lenses or spectacles. However, because the soft contact lenses are produced from relatively fragile materials they are susceptible to damage or deterioration unless they are properly cleaned and treated on a regular basis. A preferred cleaning treatment requires that the wearer rinse the lenses with a sterile saline solution. The lenses are then cleaned with a further solution to remove deposits from the lenses. Thereafter, the lenses are inserted into a carrying case which contains a quantity of sterile saline solution. The carrying case is then placed in a heating apparatus and the lenses are subjected to sufficient heat for an appropriate period of time to properly disinfect them for future wear.
The delicate nature of the soft contact lenses make them much more susceptible to damage than contact lenses made from hard materials. Therefore, the rinsing solutions and cleaning techniques used are very important and must be performed properly for the integrity of the lenses to be maintained.
The proper rinsing of soft contact lenses is essential to insure that substantially all of the cleaning solutions and other foreign substances are removed from the lenses before the lenses are inserted in the eyes of the wearer. If the proper cleaning and rinsing procedures are not followed the wearer may suffer from eye irritation, inflammation or worse.
It should be noted that the present invention, while intended to be used in conjunction with the cleaning and rinsing of soft contact lenses, may easily be used in the cleaning and rinsing maintenance procedures required by the hard contact lenses.
It, therefore, is fairly evident that as the number of people who wear soft contact lenses continues to increase dramatically, the need for proper cleaning tools and materials also continues to rise.
Many of the containers used for storing and dispensing sterile saline solutions comprise squeeze bottles which the user would normally use by inverting the bottle and squeezing the sides which, in turn, forces the sterile solution out of the dispensing orifice. There is no provision with this type of container to keep it in an upright position while dispensing the liquid, nor is there any provision to dispense more solution than can be emitted with a single squeeze. If more solution is required, the user must continually release pressure so the sides of the bottle may again be squeezed to force out another stream of liquid, the velocity of which will initially be intense and then taper off.
A further drawback to a squeeze-bottle arrangement is that as the squeezing pressure is released, air is drawn back into the bottle. This allows outside contaminants to enter the bottle and to, perhaps, contaminate the contents of the bottle.
Other containers are readily available on the marketplace which are specifically designed for dispensing sterile unpreserved saline solution. This type of container is generally referred to as "unit dose" or "single dose" and is specifically packaged for people who, for whatever reason, cannot tolerate the preserved saline solution. As the name implies, the contents of this type of container must be used entirely after the container is opened, or whatever remains of the unpreserved solution must be thrown away. This is because the solution in the dispenser is unpreserved and once the container is opened it is subject to contamination by being exposed to outside elements. If the unpreserved saline solution is allowed to be reused the contents may be contaminated and the user would unnecessarily be subjecting himself to the possibility of eye irritation or infection.
Because the container is for a single dose, each dispenser must be individually packaged which increases the cost of the solution dramatically. The amount of material needed to package the solution is quite high when compared to the volume of the solution being packaged. The material generally contains aluminum foil which prevents the solution from permeating out the container walls and is quite costly to manufacture per unit volume of solution packaged.
A further container has been introduced to the marketplace which claims to prevent oxygen and contaminants from entering the container. This container has a bellows body with a one-way valve at the top. As pressure is applied to the bellows body by the user, the material in the container is forced up to the one-way valve, which then opens to emit the liquid. As pressure is released from the bottle, the valve closes and restricts the liquid flow. It would appear that the one-way valve of this container is formed from an elastic material that has memory. That is, as pressure is applied to the bellows the valve material distorts to cause an opening for the liquid to pass through. When pressure is released from the bellows the memory of the elastic valve causes it to return to its original shape, which in turn closes the aperture, stopping the liquid flow.
In this type of bottle a substantial amount of pressure will have to be applied to the bellows in order to overcome the memory of the valve to cause it to open. Once the valve is open, the pressure must be maintained by the user or the flow of liquid will cease.
A further drawback to the above type of fluid dispenser is that when pressure is released from the bellows the valve does not immediately close. This allows outside contaminants to be drawn back into the container, thereby contaminating the contents.
The liquid, or solution, storing and dispensing apparatus, comprising the present invention, overcomes the above-mentioned difficulties.
There have, of course, been other types of dispensing apparatus which have been used for dispensing various and sundry other types of solutions which run the gamut from house paints to water. However, dispensers for these liquids generally do not contemplate maintaining the sterility of the contained material nor do they offer the compactness or portability needed for dispensing sterile solutions, such as would be necessary for caring for contact lenses. Some examples of these types of dispensers are shown in U.S. Pat. No. 103,640 entitled "Improved Apparatus for Painting", issued to A. P. Merritt on May 31, 1870; U.S. Pat. No. 720,902 entitled "Apparatus for Making Relief Work" issued on Feb. 17, 1903 to H. Du Brau and U.S. Pat. No. 1,959,782 entitled "Water Carrier and the Like", issued to F. F. Fenwick, Jr. on May 22, 1934.